Pressing machine with movable safety guard



April 26, 1960 w. c. WILSON ET AL 2,934,189

PRESSING MACHINE WITH MOVABLE SAFETY GUARD Filed May 19, 1958 3Sheets-Sheet 1 .1 for)? April 1960 w. c. WILSON ETAL 2,934,189

PRESSING MACHINE WITH MOVABLE SAFETY GUARD Filed May 19, 1958 3Sheets-Sheet 2 April 26, 1960 w. c. WILSON ETAL 3 Sheets-Sheet 3PRESSING MACHINE wrrrr MOVABLE SAFETY GUARD William Courtney Wilson andRobert H. Anderson, Chicago, Ill., assignors to Pyroxylin Products, IncChicago, Ill., a corporation of Illinois Application May 19, 1958,Serial No. 736,075

11 Claims. (Cl. 192-134) The present invention relates generally toelectrically controlled presses having a pressing element movable to andfrom a pressing location, and particularly to such a press incorporatingnumerous safety devices and designed for thermosealing patches ongarments, as in a laundry or cleaning establishment.

Presses in general are frequently operated by persons who becomeincautious and who are, therefore, subject to injury by being caughtbetween the pressing element, or in case of a heated platen, of beingburned by inadvertent contact with the platen.

The present invention relates to such a press which is operated bycompressed air and which is provided with a safety device to protect theoperator, and which is electrically controlled- Thermosealing of patcheson garments is a well established practice, but it is commonly a handoperation resulting in many variations from uniform results. Not onlythe pressure applied by hand, but the temperature and time lead tonon-uniformity. Additionally, the garment structure as to buttons, seamsand the like, lead to lack of uniformity within a single patch. Thepresent invention provides a machine which overcomes these numerousdisadvantages and a machine which may be operated by unskilled helpwithout danger of injury.

It is the general object of the invention to provide a pressing machinecapable of repeating operation under predetermined conditions, such astime, pressure and temperature, when heating is involved.

It is a further object of the invention to permit operation of the pressonly when the safety device is in its protective position.

arm

It is a further object of the invention to provide an automatic timerfor the pressing action and further to have the timer take over fullcontrol and ending of the pressing cycle from the operator afterinitiation thereof by the operator as well as resetting the press forthe next operation.

It is a particular object of the invention to provide a thermosealingpatching press which applies substantially uniform pressure overobstructed areas of a garment, such as at seams and buttons, as well asat unobstructed areas.

Various other and ancillary objects and advantages of the invention willbecome apparent from the following description and explanation of apress embodying the features of the present invention.

Although the present invention may be embodied in presses of variouskinds for various kinds of pressing operations, the invention isillustrated by a machine which is designed particularly for applyingheat-sealed patches to garments. Such a machine has utility particularlyin laundries and cleaning establishments where garments being cleanedare found to be torn and are, therefore, mended before delivery.Garments, such as workmens clothing, are most commonly subject to suchoperations. ,Patches have long been known for various sizes and ofvarious materials, provided with a thermosetting or thermoplasticadhesive so that a suitable patch maybe placed over-a garment to bemended and the patch sealed on by heat and appropriate pressure. Suchpatches have heretofore been applied by a hand iron. This method has notbeen satisfactory for garments, such as shop uniforms, because the timeof pressing, the pressure, and the temperature of the iron all vary, notonly as to different operators, but from one patch to another with thesame operator. As a result, some patches stay in place during launderingand some come off the garment. Such a machine is shown in the drawings,in which:

Fig. 1 is a perspective View of the press as positioned for operation.

Fig. 2 is a view of the same press shown in Fig. 1 as positioned inpressing.

Fig. 3 is a diagrammatic representation of the parts coupled with theelectrical connections therefor.

It is to be understood that the invention is not limited to or by theillustrative embodiment shown in the drawings, and that numerous changesand modifications are contemplated as falling within the scope of theinvention as expressed in the appended claims.

The assembly shown consists of more than one pressing platform on whichwork is placed to be pressed, and a movable arm carrying the pressingplate, so that while the platen functions on one platform, the other orothers may be cleared from a previous pressing operation and be readiedfor a pressing operation.

The pressing platen moves vertically with respect to the platform aswell as horizontally from one to another. The preferred mounting of theplaten for these move ments includes a generally horizontal arm swingingabout a vertical axis, and a vertically movable, carrier for the platenproper fixed on the horizontal arm. Where the movable platform swingsabout a vertical axis, the several platforms radiate from that axis. Theaxial region may be employed for mounting certain controls for the pressso that they remain in a fixed position.

The platen is raised and lowered by an air-operated piston electricallycontrolled. The electric control is such that once operation of thepress is initiated by closing a circuit, the platen moves onto the work,remains for a set time, is withdrawn, and the circuit opened for arepeated operation.

Safety means is provided such that the space between the platen and theplatform is closed against accidental entry by the o perators hands,while the platen moves onto the platform and remains there. This iseffected by a movable cage, which is so mounted that the heated platenis always upwardly within the cage, again to prevent accidental contactwith the platen. A feature of the cage is the regulation of itsmovements.

The cage is arranged to have alocked idle position and a normally stableprotective position, to be unlocked manually from idle position to fallinto the protective position, to be locked in protective position by thearrival of the platen, to be moved by the rising platen to locked idleposition, and in idle position to be ready for a repeated operation.After leaving idle position, and prefably upon reaching protectiveposition, the cage is employed automatically to close the controllingcircuit.

The foregoing functions are satisfied by a machine having two radialbase legs 10 and 11 forking from a central axial region 12. The legshave pressing platforms 13 and 14 preferably of molded resilientsilicone foam blocks.

The axial region 12 has a fixed post 16 to which a hori zontallyswinging arm 17 is mounted on a vertical axis. The free end 18 of thearm 17 carries an upwardly extending cylinder 19 in which is housed avertically movable piston 20. Air pressure is used to raise and lowerthe piston in a conventional manner, and thus air pressure serves toprovide and maintain the pressing pressure. The

lower end of the piston carries a working element, such as pressingplaten 21, within which is an electrical heating element 22thermostatically controlled so as to maintain apredeterminedtemperature. In Fig. 3 the numeral 23 designates diagrammatically athermostat control.

The apparatus is arranged for complete safety in operation. When thepressing platen is in its uppermost position above a work piece on aplatform, the pressing element 21 may not be lowered by action of thecylinder 19 until a safety device, preferably in the form of a cage 25,is in its protective position. The safety cage 25 is mounted on avertically swinging arm 26 pivoted at 27 adjacent the inner end of thehorizontal arm 17. The cage 25 is formed so that it completely surroundsthe heated pressing platen in a manner to prevent an operator insertinga hand or arm into the path of the pressing platen zl, or in contactwith the heated platen. When the safety cage 25 is in its raisedposition, the apparatus is electrically inoperative, and when the cage25 rests in its protective position by' its own weight, it closes aswitch 40 which initiates operation, as described hereinafter.

The cage 25 and the platen are associated by an automatic latchingmeans. Pivoted to the cage at 31 (Fig. 3) is a vertical manual lever 32projecting upwardly with a knob 33 to be grasped by the operator to bemoved into dotted line position 34 (Fig. 3), against the tension ofspring 35. The lower end 36 of the lever 32 normally rests on a ledge 37carried by the platen 21, so that the platen holds the cage in its idleposition. Manual movement of the lever releases the latch and lets thecage fall into the position shown in Fig. 2, in which position thespring 35 effects latching the cage to the platen for movement upwardlyto the position of Fig. 1 by the platen 21. When the platen reachesprotective position it closes a switch 40 as shown in Fig. 2. Theclosing of switch 40 energizes a solenoid valve 41, which then causesair pressure to move the piston 20 down.

The air pressure is provided from a main supply42 through a cleaner 43,through a reducing valve 44, and through an oiler 45 which introducesdrops of oil into the passing air to lubricate the piston. The air thenpasses via conduit 46 to a T-fitting 47 which discharges via coupling 48into solenoid valve 41 and via coupling 49 to a manifold 51 at the topof cylinder 19.

The manifold is associated with valve means which has two positions-oneto introduce air to the top of the cylinder and vent air. from thebottom of the cylinder and the other, to introduce air to the bottom ofthe cylinder and vent air from the top of the cylinder. Any conventionalvalve mechanism for this purpose may be employed. Such a valve structureincludes a sliding valve member 52, shown more or less diagrammaticallyin Fig. 3. In the position shown, the valve member 53 permits air toenter the bottom of the piston via conduit 53, but, when moved to theleft in Fig. 3, it uncovers port 54 and lets air move the piston 16downwardly. The valve is so moved to the left by a diaphragm S in acasing 56 which diaphragm is normally urged to the right by a spring 57.The numeral 58 indicates a connecting link from the slide valve 52 tothe diaphragm 55. Numeral 59 represents a small hole in the casing 56 onthe pressure side to vent air at a rate slower than air is supplied viatube 60 connecting the solenoid casing 41 with the casing 56. Solenoidvalve 41, when energized, lets air pass from tube 48 into tube 60 tomove the diaphragm 55 to the left. When the solenoid is not energized,the spring 57 moves the diaphragm to the right and hence the slide valve52, thus causing the piston to rise. Suitable exhaust holes 62 and 63from the cylinder are indicated but the connections thereto areconventionally involved in the slide valve.

For automatic operation following the closure of switch- 46. there isincluded a standard timing clock for opening the circuit to the solenoidvalve 41 after a preset time.

The timer is represented generally by the dotted line block 65. It has aclock motor which runs when the switch 40 is closed. The clock operatesto open a normally closed timed switch in series with the switch 40 andsolenoid valve 41. The opening'action takes place after a preset runningtime for the clock to deenergize the solenoid valve 41, and then after ashort interval of a fraction of a second the timed switch closes and theclock returns to starting position. During said short interval, thedeenergization of solenoid valve will have caused the cage 25 to risewith the platen and thereby open switch 40. Thus, on return of theplaten to idle position the press is ready for a repeating operation.

The timing clock above described is a standard one capable of numerousinternal and external electrical connections for ditferent results.Those presently utilized are now described. Numeral 66 represents theclock and numeral 67 the pointer manually set for a chosen period of thepressing operation. Numeral 68 represents the normally closed switchopened by the timer, with leads 69 and 70 to'it.

The main power leads '72 and 73 supply outlet box 74 into which thecable 75 to the heating element 22 may be plugged. They then lead to atwo-wire cut-ofi switch 76 mounted on post 16, from which the line 77leads to the clock 67 and connection 70. Line 78 leads to the switch 40from which line 79 leads to the clock and line 80 leads through thesolenoid valve 41 to line 69.

In operation, when work is placed on one pad 12 or the other 13, the arm17 is swung over the work, and knob 33 pushed inwardly. This unlatchesthe cage at the ledge 37, allowing the cage to drop into place. Afterthis, and preferably at the bottom of its fall for reasons given later,it closes switch 40. This energizes solenoid valve 41 through thenormally closed switch 68 in the timer, and air pressure forces thepiston and platen down. When down the ledge 37 again latches onto thelever 32 at its end 36. The platen remains down so long as the solenoidremains energized and this time period is controlled by the set ofpointer 67 on its dial. The clockwork then opens switch 68, whichdeenergizes solenoid valve 41 causing the platen to rise and lift thecage. The up stroke of the cage opens switch 40, which act must takeplace at a proper time relative to the time that switch 68 returns toits normally closed position. Because the responses are notinstantaneous, depending upon pneumatic passages of air, the opening ofswitch 40 and the resetting of the timer switch 68 must be relativelytimed with respect to the responses of the press. For this reason, theswitch 40 is operated at the bottom point of fall of the cage;

However, it is to be understood that other but standard electricalequipment is available for by-passing switch 40 immediately after itsclosure, to take over control of the cycle and thereby destroy thecontrolling function of the cage. In the present instance where theplaten moves between idle and pressing positions in about one-second,the location of switch 40 as disclosed gives adequate return time forthe timer switch 68, which resets in about second. The disclosedarrangement is preferred to one in which the full pressing time iscontrolled wholly by the time clock. By compelling the energizingcurrent during the entire operation to pass through the switch 40, theopera tor may always retract the platen merely by lifting the cage toopen switch 40. So breaking the circuit to the timer 65 will cause it toreturn to normal starting position even though it has not completed itsset advance.

This application is a continuation-in-part of applica' tion Serial No.531,455, filed August 30, 1955.

We claim:

1. A press comprising a fixed horizontal platform, a platen verticallymovable from idle position into pressing position over and toward saidplatform and away from said platform, a protective cage associated withsaid platen and vertically movable by gravity from idle position towiththe cage and the platen for holding the cage in idle position duringthe idle position of the platen and arranged for moving the'cage fromprotective to idle position by movement of theplaten from pressing toidle position, said latching means being releasable manually fromlatching position when the platen is out of pressing position, anelectric circuit, an electric control switch in said circuit arranged toclose the circuit by action of the cage when moving out of its idleposition to protective position, a solenoid insaid circuit,platen-moving means normally urging-said platen into idle position andassociated with said solenoid to move the platen out of idle positioninto pressing position and to hold it in pressing position only duringenergizing of said solenoid, a timing clock actuated to run for a presettime upon closing said switch, a timed switch in said circuit normallyclosed and arranged to be opened at said preset time by said clock andthen automatically to-close after a preset interval of time, wherebysaid timed switch on opening deenergizes the solenoid, resulting invertical movement to the idle positions of the platen and the cagelatched therewith, and resulting in opening of the control switch priorto the expiration of said preset interval of time.

2..A press comprising a fixed horizontal platform, a platen verticallymovable from idle positioninto pressing position over and toward saidplatform and away from said platform, a protective cage associatedwith'said platen and vertically movable by gravity from idle position toprotective position to guard the space between the platform and theplaten, automatic latching means associated with the cage and the platenfor holding the cage in idle position during the idle position of theplaten and arranged for moving the cage from protective to idle positionby movement of the platen from pressing to idle position, said latchingmeans being releasable manually from latching position when the platenis out of pressing position, an electric circuit, an electric-controlswitch in said circuit arranged to close the circuit by action of thecage when moving out of its idle position to protective position, asolenoid valve in said circuit, a pneumatically operated platen-carryingpiston and a cylinder therefor arranged to move the piston in bothdirections by alternative connections of air pressure to the cylinder,means providing a supply of air under pressure, said solenoid valve whenenergized establishing air connection from said supply to one end ofsaid cylinder to move the platen from idle to pressing position and tohold it in pressing position only during energizing of said solenoidvalve, said solenoid valve being normally biased when deenergized toestablish air-connection from said supply to the other end of saidcylinder to move the piston to idle position, a timing clock actuated torun for a preset time upon closing said switch, a timed switch in saidcircuit normally closed and arranged to be opened at said preset time bysaid clock and then automatically to close after a preset interval oftime, whereby said timed switch on opening deenergizes the solenoidvalve, resulting in vertical movement to the idle positions of theplaten and the cage latched therewith, and resulting in opening of thecontrol switch prior to the expiration of said preset interval of time.

3. A press comprising a plurality of fixed horizontal platforms, aplaten for movement to a position over each platform, a movable membercarrying said platen for movement to each of said positions, said platenbeing vertically movable from idle position into pressing position overand toward a platform and away from said platform, a protective cageassociated with said platen and vertically movable by gravity from idleposition to protective position to guard the space between a platformand the platen, automatic latching means associated with the cage andthe platen for holding the cage in idle posi- 6 tion during the idleposition of the platen and arranged for moving the cage from protectiveto idle position by movement of the platen from pressing toidleposition; said latching means being releasable manually from latchingposition when the platen is out of pressing position, an

electric circuit, an electric control switch in said circuit arranged toclose the circuit by action of the cage when moving'out of its idleposition to protective position, a solenoid in saidcircuit,platen-moving means normally urging said platen into idle position andassociated with said solenoid to move the platen out of idle positioninto pressing position and to hold it in pressing position only duringenergizing of said solenoid, a timing clock actuated to run for a presettime upon closing said switch, a timed switch in said circuit normally.closed and arranged to be opened at said preset time by said clock andthen automatically to close after a preset interval of time, wherebysaid timed switch on opening deenergizes the solenoid, resulting invertical movement to the idle positions of the platen and the cagelatched therewith, and resulting in opening of the control switch priorto the expiration of the said preset interval of time.

4. A press according to claim3 in which the plurality of platforms areradially located the same distance from a vertical axis, and in whichthe movable member carrying the platen swings about the axis.

5. A press comprising a fixed horizontal platform, a platen verticallymovable from idle position into pressing position over and toward saidplatform and away from said platform, a protective cage associated withsaid platen and vertically movable by gravity from idle position toprotective position to guardthe spacev between the platform and theplaten, automatic latching means associated with the cage and the platenfor holding the cage in idle position during the idle position of theplaten and arranged for moving the cage from protective to idle positionby movement of the platen from pressing to idle position, said latchingmeans being releasable manually from latchingposition when the platen isout of pressing position, an electric circuit, an electric controlswitch in said circuit arranged to close the circuit by action of thecage when moving out of its idle position to protective position, asolenoid valve in said circuit, a pneumatically operated platen-carryingpiston and a cylinder therefor arranged to move the piston in bothdirections by alternative connections of air pressure to the cylinder,said I solenoid valve when energized establishing air connection to movethe platen from idle to pressing position and to hold it in pressingposition only during energizing of said solenoid valve, a timing clockactuated to run for a preset time upon closing said switch, a timedswitch in said circuit normally closed and arranged to be opened at saidpreset time by said clock and then automatically to close after a presetinterval of time, whereby said timed switch on opening deenergizes thesolenoid valve, resulting in vertical movement to the idle positions ofthe platen and the cage latched therewith, and resulting in opening ofthe control switch prior to the expiration of said preset interval oftime.

6. A press according to claim 5 in which there are a plurality ofhorizontally spaced platforms radially located the same distance from avertical axis, and in which there is a movable member carrying saidplaten, said movable member being mounted to swing about said axis.

7. A press according to claim 5 in which said platform is a siliconefoam.

8. A press according to claim 5 in which there are a plurality of spacedplatforms of silicone foam radially located the same distance from avertical axis, and in which there is a movable member carrying saidplaten, said movable member being mounted to swing about said axis.

9. In a pressing machine a pair of coacting relatively moving pressingmembers normally biased into non-press? ing position, press-closingmeans including a fluid actuated motor and motion transmitting mechanismfor moving one of, said members into pressing engagement with the othermember, conduit means for the supply and exhaust'of motive fluid to andfrom said motor and including a normally closed inlet valve and anormally opened outlet valve, a solenoid arranged when energized to movesaid valve means to press-operating position with said inlet valve openand said outlet valve closed, and when deenergized to reverse thepositions of said valve and thereby effect movement of the pressingmembers to their normally biased position, a protective cage normallybiased to move into a protective position surrounding said pressingmembers and movable out of said position to an idle positioncorresponding to the normally biased positions of said pressing members,latching means be tween said cage and said pressingmembers operable toengage said cage in its normally biased position and to move it to andhold it in said idle position, said latching means being manuallyoperable to release the cage for movement to its normally biasedposition, an electrical starting switch closed by movement of said cageto its normally biased position, an electrically operated timercontaining a normally closed timed switch arranged to be opened only fora short interval of time following a preset time period beginning withenergization of said timer, said solenoid being in series with saidstarting switch and said timed switch, and said timer being energized byclosing said starting switch.

10. In a pressing machine having electrical means to be energized foractuating the machine, a safety cage and relatively movable normallyseparated pressing means movable together to press only duringelectrical energization of said electrical means, an electricallyoperated timer containing a normally closed timed switch arranged to beopened only for a short interval of time following a preset time periodbeginning with energization of said timer, a starting switch, saidelectricalmeans, said starting switch and said timed switch being inseries for conconnected to be energized by said starting switch, saidstarting switch being arranged to be closed by movement of the cage intoprotective position from idle position and being movable to idleposition by said pressing means in moving out of pressing position, andmanually releasable latching means associated with said cage andpressing members and operable to move the cage out of protectiveposition by movement of the pressing means out of pressing position.

11. In a pressing machine having electrical means to be energized foractuating the machine, a safety cage and relatively movable normallyseparated pressing means movable together to press only duringelectrical energization of said electrical means, a timer containing anormally closed timed switch arranged to be opened only for a shortinterval of time following a preset time period beginning with thetiming action of said timer, a starting switch, said electrical means,said starting switch and said timed switch being in series forconnection to a source of electric power, said cage being movable intoprotective position from idle position and being movable to idleposition by said pressing means in moving out of pressing position, saidtimer being arranged for initiation of timing action by saidcage movinginto protective position, and said starting switch being arranged to beclosed by said cage moving to protective position, and manuallyreleasable latching means associated with said cage and pressing membersand operable to move the cage out of protective position by movement ofthe pressing means out of pressing position.

References Cited in the file of this patent UNITED STATES PATENTS1,672,303 Carroll et al. June 5, 1928 2,315,151 Booth Mar. 30, 19432,324,660 Yanchenko July 20, 1943 2,341,689 Bryson Feb. 15, 19442,775,129 Peras Dec. 25, 1956

